The research programs of the major user group center on studies of the agents active in neurotransmission, on the synthesis of novel polycyclic compounds, and on the synthesis of prostaglandins and antitumor agents. The research programs are hampered at the present time by the lack of modern mass spectrometric equipment at The University of Chicago. This proposal, accordingly, is focused on the needs for gas chromatography-mass spectrometry and high resolution mass spectrometry using a variety of ionization methods for the conduct of the research programs. It is concluded that the needs of this user group would best be satisfied by a multifunction Kratos MS 80 spectrometer.